Mobile communication terminals, also known as mobile terminals, have nowadays multiple communication channels either established with different communication technologies or with different communication applications. When a user is willing to initiate a communication with a destination party he/she selects an application and the destination party and performs predetermined actions in order to initiate the communication towards the destination party. The communication channel, i.e. the technology and the application, varies according to the user selection, e.g. the selection of the application used for the initiation of the communication. For example, in case the user selects a call application in the user terminal the call may be setup through a mobile communication network and the connection utilizes a communication technology implemented in the mobile communication network.
However, the availability of multiple communication applications and communication channels has tremendously increased a complexity of the communication environment. For example, it may happen that there is a failure in a communication channel and the mobile terminal is blocked to use the communication channel in question, but the user is still selecting an application using the communication channel for initiating the communication. As a result, the user gets frustrated as the connection cannot be established.
The existing solutions provide some arrangements which enable the user to detect that a certain communication channel is not available for communication. Namely, the mobile terminals equipped with a subscriber identity module for accessing a mobile telecommunication network controlled by a telecom operator are configured to monitor a quality of the mobile communication network. The monitoring is implemented by arranging the mobile terminal to measure radio signal strength and, if possible, to switch the mobile terminal to another cell in case the signal strength is below a limit. In some situation it may turn out that none of the cells capable of serving the mobile terminal in question are able to provide acceptable signal strength and as a result the mobile terminal is out-of-service from the mobile communication network. The mobile terminal is typically configured to indicate this to the user e.g. by showing a dedicated indicator on a display.
Further, there is also introduced a solution that switches a subscriber identity in the network in case the above described situation regarding a weak signal strength with one subscriber identity is detected. Namely, a subscriber identity module may store a plurality of subscriber identities, such as IMSI (International Mobile Subscriber Identity), and a logic switching between the subscriber identities in response to a detection of un-acceptable signal strength with the subscriber identity in use. The subscriber identities differ so that the second subscriber identity represents a foreign subscriber identity to the network into which the first subscriber identity is tied to. In case the second subscriber identity is activated the mobile terminal initiates a registering procedure towards a home network of the second subscriber identity through available networks within the area the mobile terminal resides.
The known solutions have drawbacks at least in that they provide very simple process for transferring the subscriber to use a foreign subscriber identity only if the signal strength goes below a predetermined threshold level. However, the known solution does not reveal a situation if a certain communication service is not available at all even if the signal strength is maintained above the threshold level.
Hence, there is need to develop a solution by means of which it is possible to mitigate, at least partly, the drawbacks of the existing solutions.